Liquid mist fire extinguisher

ABSTRACT

A liquid mist fire extinguisher, comprising a container for holding a gas and a liquid under pressure. The extinguisher has valve assembly at the upper end of the container, a valve for simultaneously releasing said gas and said liquid separately from the container, and a hose for feeding said gas and said liquid separately through a nozzle. The nozzle assembly includes means for feeding said gas and said liquid separately through a mixing chamber, and exiting orifices in an end surface of said nozzle assembly for issue of mixed gas and liquid in a fine mist.

This application is a continuation application Ser. No. 09/306,017,filed May 6, 1999, now U.S. Pat. No. 6,189,625.

FIELD OF INVENTION

This invention relates to a liquid mist fire extinguisher and moreparticularly a low pressure water atomizing fire extinguisher.

BACKGROUND TO THE INVENTION

Fires are classified as A, B, C or D as follows: Class A: ordinarycombustibles; Class B: flammable liquids; Class C: electrical fires andClass D: flammable metals. Fire extinguishers are listed in Canada andthe United States by ULC and UL respectively according to theireffectiveness in suppressing the fires of the various classes. Astandard extinguisher with an A:B:C rating for example, is effective insuppressing A, B and C class fires.

To achieve an A:B:C rating, extinguishers to date have used either drychemicals or halon. The use of dry chemicals results in a messy andsometimes toxic cleanup. Halon is a clean alternative but has beenbanned by the Montreal Protocol on Substances that Deplete the OzoneLayer.

Water has also been used but prior art water extinguishers have notachieved an A:B:C rating. The standard water extinguisher for exampledischarges a solid stream of water from a pressurized canister and has alimited Class 2A rating.

Another type of known water extinguisher discharges a spray of waterdroplets and utilizes the same amount of water as the standardextinguisher. This extinguisher typically operates at about 100 psi.While this water extinguisher has been rated A:C, it does not generatethe fine atomized mist required for a class B rating.

WO 97 02863 to Richter, Joachim discloses a fire extinguisher and aspecially designed spray nozzle for producing a jet of extinguishingagent, wherein the extinguisher comprises a pair of containers adaptedto store carbon dioxide gas and extinguishing water, whereby upon mixinginside the spray nozzle the carbon dioxide gas causes the water dropletsto freeze, allowing for improved throwing ranges.

It is therefore an aspect of the present invention to provide anextinguisher in which water and air are stored together and are releasedsimultaneously and separately to produce a fine liquid mist, capable ofclass A:B:C rating.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided an apparatusfor producing a fine liquid mist, comprising a container (10) forholding a gas and liquid under pressure, valve means for releasing thegas and the liquid from the container, a nozzle, feed means operativelyconnecting the nozzle and the container, and a mixing chamber in thenozzle, the mixing chamber having outlet orifices for emission of theliquid mist, the outlet orifices being at a discharge end of the mixingchamber characterized in that the container having acutation means forsimultaneously actuating first and second valve means, the actuationmeans comprising a single actuation lever for simultaneously opening andclosing both of the valve means; the valve means comprising a firstvalve for controlling and regulating the flow of liquid from a containerto a first supply means and a second valve for controlling andregulating the flow of gas from the container to a second supply means,wherein simultaneous release of the liquid and the gas is achieved whenthe single actuating lever is displaced whereby movement of each of thefirst and second valves occurs, and wherein the mixing chamber includestwo separate inlets at one end, a first inlet for injection of theliquid radially into the mixing chamber and a second inlet for injectionof the gas axially into the mixing chamber for atomization of theliquid.

In another aspect of the present invention, there is provided a releaseassembly for simultaneously releasing a gas and a liquid separately froma pressurized container containing the gas and liquid and to permitfeeding the liquid and the gas as individual, separate fluid streamsfrom the container and to and through the valve, characterized in thatthe release assembly is a single actuating means connected to first andsecond valves for simultaneously actuating the valves, the first valvefor controlling and regulating the flow of liquid from a container to afirst supply means, the second valve for controlling and regulating theflow of gas from the container to a second supply means, and wherebymovement of the single actuating means effects opening a closing of thevalves to effect control and regulation of flow of the liquid and thegas.

In a further embodiment of the present invention, there is provided aliquid mist fire extinguisher, comprising a container for holding a gasand a liquid under pressure, a valve assembly at an upper end of thecontainer for releasing the gas and the liquid from the container, ahose and a nozzle assembly, characterized in that the extinguisher has asingle actuating means for simultaneous release of the liquid and thegas by simultaneously actuating first and second valve means, theactuating means controlling spaced apart first and second valves, andwherein the valve means simultaneously releases the gas and the liquidseparately from the container, the first valve means controlling andregulating the flow of liquid from a container and the second valvecontrolling and regulating the flow of gas from the container.

In an apparatus for dispensing a gas and a liquid from a containerholding the gas and liquid, the improvement wherein the containerincludes a body having separate outlets for dispensing each of the gasand the liquid from the container, the outlet for the gas being incommunication with the gas in the container and the outlet for theliquid being in communication with the liquid in the container, firstvalve means in the body associated with the outlet for dispensing theliquid and second valve means being associated with the outlet fordispensing the gas, means to open together each of the first and secondvalve means, wherein the body includes a conduit in communication withliquid in the container, the body having a chamber in communication withthe conduit, the chamber having a conduit in communication with theliquid outlet, and wherein the separate outlets for the gas and theliquid are adapted to discharge separate gas and liquid streams from thebody upon actuation of the means to open the first and second valvemeans.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-section of a fire extinguisher according to thepresent invention;

FIG. 2 is a cross-section of the valve structure at the top of theextinguisher of FIG. 1, to a larger scale, and at right angles to thatof FIG. 1; with valve closed;

FIG. 3 is a cross section similar to that of FIG. 2, with valve open;

FIG. 4 is a cross section of the valve structure, on the axis of thecross section of FIG. 1;

FIG. 5 is a longitudinal cross section through the nozzle;

FIG. 6 is an end view on the end of the nozzle member, in the directionof arrow A.

FIG. 7 is a cross-section of another embodiment of the valve structureof the present invention, on the axis of the cross-section FIG. 1.

FIG. 8 is a cross section of another embodiment of the valve structureof the present invention, on the axis of the cross section of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The drawings illustrate a fire extinguisher assembly having an A, B andC rating comprising a pressure container 10 of, for example, anapproximately 12 L capacity having at its upper end a valve structure12, and flexible hose 14 with a relatively ridged wand portion 16, and anozzle assembly 18 at the end of the wand 16. The valve structure 12closes the upper end of the container which, in use contains a liquid,for example, water, at its lower portion 20 and a pressurizing gas, forexample, air at its upper portion 22, the gas/liquid in the phase shownat 24. A tube 26 extends down and from the valve structure 12 towardsthe bottom of container, finishing a short distance above the bottom.The tube is connected at its upper end to the valve structure 12.

FIGS. 2 and 3 show specifically the valve structure indicated byreference numeral 12. It comprises a main body 30, which is attached bya fitted threaded connection 32 to a neck portion 34 at the upper partof container 10. The body 30 has a central longitudinal extending bore,having a varying dimension along its length. At its lower end 36, thebore is enlarged and receives the upper end of the tube 26, convenientlyprovided with a threaded connection. The bore tapers inwardly to form avalve seat 38 of a first valve. The bore enlarges, at 40, to form afluid passage, described later in connection with FIG. 4. Above theenlargement 40, the bore decreases in size to form an elongate tubularseating at 42. Above the tubular seating 42, the bore is enlarged and aplug 44 is inserted to close off the bore, and also to form a chamberwhich serves as a transfer passage 46, again described in more detailwith respect to FIG. 4. The plug 44 has a central bore 48 and extendingthrough the bore is an elongate valve member or stem 60. At its lowerend, the valve stem 60 has a tapered valve member or seal 62, whichcooperates with tapered valve seat 38. At an intermediate position,there is provided a second valve comprised of an extended valve portion64 which cooperates with the tubular seating 42.

The first valve comprised of valve member or seal 62 and valve seat 38acts to control flow of liquid from container. The second valve formedof the upper end of the valve portion 64 acts with the upper end ofseating 42 to control flow of gas from the container 10.

A further bore 70 extends up through the body 30 and connects to aradial bore 72 extending to the central bore to form a port 76, betweenthe enlargement 40 and the passage 46. The outer end of the radial bore72 is closed by a plug 78 which can be used to provide a connection to apressure gauge. Considering the valve portion 64, a reduced diameterportion 66 on the valve member 60 connects with the passageway 46 only,in a closed position, as in FIG. 2, and connects passageway 46 with port76, in an open position, as in FIG. 3.

The upper end 80 of the valve member 60 extends beyond the plug 44. Alever 82 (see FIG. 1) is pivotally mounted on the end of the stem 60 andextends over the outer end 80. A compression spring 81 is mounted on theouter end 80 of the valve member 60 to bias the valve member to a closedposition. Pressure by the lever 82 on the outer end 80 of the valvemember 60 will open both valves simultaneously. Various seals areprovided for the valve member 60. An O-ring 84 is provided between thepassage 46 and the upper end surface of the body 30, in the example ofthe plug 44, to prevent leakage from the top end or upper surface of thebody 30. O-rings 86 and 88 are spaced apart to prevent leakage from port76 to the passage 46 and enlargement 40 in the valve closed position,and to prevent leakage from the port 76 to the enlargement 40 in thevalve open position. O-rings 100 and 107 can be provided in aconventional manner, such as to seal threaded connections 32 and thethreaded connection between the plug 44 and the upper end of the body30.

FIG. 4 illustrates the attachment of the flexible hose 14 to the valvebody 30, with connections to the enlargement 40, and also connection ofa flexible tube 110, inside the hose 14 to the passage 46. The hose 14is connected to the body 30 via a threaded connection 112 in a bore 114connecting to the enlargement 40. The tube 110 extends up through a bore116 in the top part of the body 30 to connect to the passage 46. As seenin FIG. 1, the tube 110 extends through the hose 14 and wand 16 to anozzle assembly 18.

When the valves are closed, neither the liquid nor gas can flow from thecontainer 10 to the nozzle assembly 18. Pushing down on the lever 82opens the valves to a position as seen in FIG. 3. Liquid escapes up pastthe lower end of the valve member 60 into the enlargement 40 and upthrough bore 114 and connection 112 into the hose 14. Simultaneously,air escapes through bores 70 and 76, recess 66, passage 46 and thenthrough the tube 110 to nozzle 18.

One form of nozzle assembly 18 is illustrated in FIG. 5. This assemblyhas a nozzle member 120 attached to the end of the wand 16 and aninternal intermediate support member 122 to which the tube 110 isconnected. The member 122 includes an orifice or bore 128 formedinternally of the member 122, and can be, e.g., 0.75–1.5 mm in diameter.

The member 122 is connected to the nozzle member 120 forming an axialhollow or mixing chamber 126. A passage 124 provides access, via a port125, to a mixing chamber 126 for the liquid in the wand 16. Port 125,can be, e.g., 2–3.5 mm in diameter. Liquid enters the mixing chamber 126through the port 125 at right angles to the longitudinal axis of thenozzle 18. Gas flows through bore 128 of the member 122 into the mixingchamber 126 and interreacts with the liquid, for effective atomizationof the liquid.

The nozzle member 120 is circular in cross section, and has a closed endwith a number of orifices 132. One arrangement is seen in FIG. 6. Thenozzle member 120, at one end of the nozzle assembly 18 has, when seenin cross section (FIG. 5) with respect to the longitudinal axis, anangled face 130, the angle being preferably in the range of 60° to 75°.

The gas enters the mixing chamber in a longitudinal direction andcombines with the jet of liquid that is entering the mixing chamber atport 125. Thus, this will produce a gas/liquid mixture. The mixtureexits the chamber 126 through the orifices 132, resulting in furtherexpansion and further atomization of the liquid. The orifice pattern 132combined with the amount of atomization and end face angles produces thedescribed mist pattern.

To charge the container 10, about 6 L of liquid, for example water isplaced in the container. The gas, for example air, is fed into the upperpart of the container 10 through the wand 16 by removing the nozzle 120and replacing it with an air valve (not shown). The gas source means isconnected to the air valve, the valves are opened and air is fed intothe container 10. After pressurization, the nozzle is replaced.Pressurization in this manner minimizes later tampering. As analternative, the gas is fed through bore 72 by removing plug 78. As afurther alternative, a pressure gauge can be permanently mounted at thebore 72, and this can be provided with a T-shaped valved connectionhaving an air valve for connection of a pressurized source of gas. Thegas is generally pressurized initially to a maximum pressure of about175 pounds per square inch.

FIG. 7 illustrates an alternate embodiment of the valve structure 12.The central longitudinal extending bore above enlargement 40 is notenlarged, eliminating the need for a plug such as plug 44 (see FIG. 4)to close off the bore. The bore 116 extends through the top of the valvebody 30. The top of the bore 116 is closed by a plug 31. A second bore33 serves as a transfer passage in place of the chamber 46 (see FIG. 4),and is closed by plug 37. The valve structure 12 is otherwise the sameas the previous embodiment including the tube 110 which extends upthrough bore 116.

FIG. 8 illustrates a further alternative embodiment of the valvestructure 12. The central longitudinal extending bore above enlargement40 is not enlarged eliminating the need for a plug such as plug 44 (seeFIG. 4) to close off the bore. Also eliminated is bore 116 (see FIG. 7).A bore 33 serves as a transfer passage in place of the transfer passageor chamber 46 (see FIG. 4), and is connected through a connection 112Ato a flexible hose 14A. As with previous embodiments of the presentinvention, when the valves are closed, neither the liquid nor gas canflow from the container 10. In use, with similar components describedabove, pushing down on a lever opens the valves whereby liquid escapesup past the lower end of the valve member into the enlargement and upthrough the connection and into the hose. Simultaneously, air escapesthrough suitable bores or the like, through a transfer passage and thenthrough the connection 112A to the hose 14A.

A carrying handle can be attached through the valve structure 12 as seenin FIG. 1. The container is shaped so that such can normally standupright on a surface.

Although embodiments of the invention have been described above, it isnot limited thereto and it will be apparent to those skilled in the artthat numerous modifications form part of the present invention insofaras they do not depart from the spirit, nature and scope of the claimedand described invention.

1. In an apparatus for dispensing a gas and a liquid from a containerholding said gas and liquid, the improvement wherein the containerincludes a body having separate outlets for dispensing each of said gasand said liquid from said container, said outlet for said gas being incommunication with the gas in the container and the outlet for theliquid being in communication with the liquid in the container, firstvalve means in said body associated with said outlet for dispensing saidliquid and second valve means being associated with said outlet fordispensing said gas, means to open together each of said first andsecond valve means, wherein said body includes a conduit incommunication with liquid in said container, said body having a chamberin communication with said conduit, said chamber having a conduit incommunication with said liquid outlet, and wherein said separate outletsfor said gas and said liquid are adapted to discharge separate gas andliquid streams from said body upon actuation of said means to open saidfirst and second valve means.
 2. The apparatus of claim 1, wherein saidbody includes a transfer passage between said outlet for said gas andsaid second valve means for dispensing said gas.
 3. The apparatus ofclaim 2, wherein said transfer passage includes a bore perpendicular tosaid transfer passage, one end of said bore being connected to saidtransfer passage and the other end of said bore being in communicationwith the exterior of said body, and plug means for closing said bore atsaid other end.
 4. The apparatus of claim 1, wherein said outlets fordispensing said gas and said liquid are each connected to separateexterior conduits to convey separate streams of said liquid and saidgas.
 5. The apparatus as claimed in claim 1, said first and said secondvalve means comprising an extended stem portion which is movable to openand close said outlets to dispense said gas and said liquid as separatestreams.
 6. The apparatus according to claim 1, wherein said first andsecond valve means are connected to each other in operative associationto simultaneously release said gas and said liquid as separate streamsfrom said container.
 7. The apparatus according to claim 1, furtherincluding an elongate valve member, wherein said first valve means isformed at one end of said valve member, said second valve means formedat a position intermediate the other end of said valve member and saidfirst valve means, said means for opening each of said first and secondvalve means positioned at the other end of said valve member.